LNG Power Research Articles

A study on the Emission Characteristics of FPM and CPM in Power Plants

As people have become more aware of fine particulate matter (PM2.5) recently, there have been growing concerns over the harmful impact of PM2.5 on human health. Since stationary sources are a major source of PM2.5 emission, measures to manage and reduce PM2.5 emission from the stationary sources need to be taken. PM2.5 primary emissions from stationary sources contain a filterable and condensable portion. Filterable PM are particles directly emitted from a stack in a solid or liquid form at stack conditions and captured in the filter of a sampling train. Condensable PM is a material that stays as gas within the stack but is condensed, diluted and/or cooled into solid or liquid particles in the ambient air immediately after discharge from the stack. In this study, the emission characteristics of filterable and condensable PM from power plants are investigated. The average filterable PM2.5 concentration from two coal-fired power plants ranged from 1.85 to 2.02 mg/m3 and that from an LNG power plant was 0.02 mg/m3. The average condensable PM2.5 concentrations from the coal-fired power plants and the LNG plant were 9.08-12.20 mg/m3 and 1.02 mg/m3, respectively.

Opportunities and Challenges for the Industrial Titanium Market

The industrial titanium market is the second largest segment of the titanium industry and currently comprises less than 20 % of the overall titanium market. In spite of a more than 50 year history of successful application in corrosive environments myths about availability, fabrication, pricing and corrosion resistance are still part of the conversation and culture with many potential customers. The author will discuss these issues and present comparisons with other common materials of construction to demonstrate the business case for titanium. With seawater/brackish water being the most common corrosive environment where titanium is applied examples of current applications will be presented. By highlighting the characteristics of titanium that led to the material choice in these examples potential new applications can be identified. These examples will come from application on offshore platforms, LNG liquefaction plants, power generation, desalination and petroleum refining operations. Against the backdrop of the application analysis the author will also explore regulatory, market influences and new technology impacting the industrial titanium market segment. Drawing on statistics from the Titanium Association and other resources a projection for industrial growth will be presented for the next decade.

Design and Optimization of a Full-Generation System for Marine LNG Cold Energy Cascade Utilization

This paper took a 100,000 DWT LNG fuel powered ship as the research object. Based on the idea of “temperature matching, cascade utilization” and combined with the application conditions of the ship, a horizontal three-level nested Rankine cycle full-generation system which combined the high-temperature waste heat of the main engine flue gas with the low-temperature cold energy of LNG was proposed in this paper. Furthermore, based on the analysis and selection of the parameters which had high sensitivity to the system performance, the parameters of the proposed system were optimized by using the genetic algorithm. After optimization, the exergy efficiency of the marine LNG gasification cold energy cascade utilization power generation system can reach 48.06%, and the thermal efficiency can reach 35.56%. In addition, this paper took LNG net power generation as the performance index, and compared it with the typical LNG cold energy utilization power generation system in this field. The results showed that the unit mass flow LNG power generation of the system proposed in this paper was the largest, reaching 457.41 kW.

Off-design analysis of a CO2 Rankine cycle for the recovery of LNG cold energy with ambient air as heat source

In this paper, a novel simple CO2 Rankine cycle to recover LNG cold energy is proposed. The system is driven by ambient air, which is regarded as one of the most convenient and economic heat source. For the reason that the ambient temperature changes with days and seasons, it is necessary to take into account the system behavior with the variations of ambient temperature and mass flow rate. In this study, a detailed off-design performance analysis based on the preliminary design of the system is carried out. A sliding pressure control method is applied to keep the system stably and safely operate at off-design conditions. And the system behavior at design condition are compared with that under off-design conditions using a statistical tool. It is noted that the design value of temperature and mass flow rate of ambient air is 313.15 K and 26.86 kg·s−1. The results indicate that the design cycle thermal efficiency, cold energy recovered from LNG and net power output is 6.75%, 1500.7 kW and 108.7 kW, respectively. With the decrease of ambient air temperature and mass flow rate, almost all the performance indicators decrease. But pump power consumption and efficiency changes slightly. Compared with the design values, cycle thermal efficiency and net power output decreases up to 47% and 60% when the ambient temperature decreases to 293.15 K, and 64% and 75% when the mass flow rate of ambient air decreases to 16 kg·s−1, respectively. Moreover, the smaller mass flow rate of ambient air has greater impact on the system performance than the bigger one.

Synergistic Emission Reduction of SO2 and CO2 Based on Clean Energy Replacement in ports

China’s energy-saving emission reduction policy calls for improved air quality while reducing greenhouse gas emissions. This paper takes the container terminal as the research object, the energy saving and emission reduction of clean energy alternative fuels such as solar energy, wind energy, geothermal energy, LNG and electricity are studied through the combination of energy substitution and emission factors. In particular, SO2 and CO2 Synergistic mitigation effect. The results show that the reduction SO2 and CO2 is positively correlated with the usage of clean energy amount. Among them, LNG has the greatest contribution to the coordinated emission reduction of SO2, and solar energy contributes the most to CO2 reduction. Our conclusion is that the use of LNG and shore power in ports can achieve better synergistic emission reductions for SO2 and CO2. And through the use of air sources, solar energy, wind energy and light energy, CO2 emission reduction effect is better than SO2 emission reduction. The Chinese government can use this method as a policy tool for energy conservation and emission reduction, and vigorously promoted the application of LNG and shore power in ports.

The effect of the arrangements for compression process and expansion process on the performance of the two-stage condensation Rankine cycle

Aiming at the problem that the irreversible loss of the condensation process for the traditional LNG power generation system is too large, this paper presents four different two-stage condensation Rankine cycles based on different arrangements of pumps and turbines. The effects of the operating conditions (the first-stage and second-stage condensation temperatures) and various working fluids on the performance of the four cycles with different structures are investigated. The results show that when the arrangement of the turbines is the same, the arrangement of the pumps (series or parallel) has little effect on the net output power. However, when the arrangement for the pumps is the same, the arrangement for the turbines has a significant effect on the net output power. When the working fluid is n-pentane and the turbines are of series arrangement, the maximum net output power is increased by about 17% compared with the condition that the turbines are of parallel arrangement. In addition, for the same cycle, whether the isentropic efficiency of turbine is a constant value or not has a significant effect on the maximum net output power, the optimal operating conditions, and the optimal working fluid.

Exergy analysis of a hydrogen and water production process by a solar-driven transcritical CO2 power cycle with Stirling engine

This study attempts to go beyond the conventional framework of the integrated solar transcritical CO2 power cycle works, aimed at further utilization of available exergy as much as possible. This paper proposed a novel system for hydrogen and fresh water production in which a Stirling engine used instead of a condenser, for the places with abundant access to solar radiation and sea, and least to freshwater sources. This proposal leads to further utilization of streams’ exergy through the system instead of wasting to the environment, and further power production by the engine followed by the higher products. The electrolyzer employed beside Reverse Osmosis (RO) desalination system, and takes full advantages of highly concentrated brine stream of desalination, eliminating the wastewater rejection through proposed system leading to attaining a near-ZLD approach in fresh water and hydrogen production. This reduces the adverse impacts of desalination’s wastewater on the environment. A thermodynamic and exergy analysis is carried out to compare the superiority of this study and investigate the effect of some key parameters on the overall performance of the system as well. The results showed that replacing the condenser by a Stirling engine reduces the exergy destruction through heat transfer from CO2 to an LNG unit. Exergy destruction was reduced from 16.7% to 8.8% for the above configuration for an ideal Stirling engine that exploits it to produce extra power which its minimum is at least 9 kW and 15 kW higher than CO2 and LNG power productions. Moreover, Entering RO brine stream, wasting 2.58 kW exergy, to the electrolyzer leads to NaClO and H2 production besides removing brine stream. In a power plant, sodium hypochlorite is used for disinfection of cooling systems and hydrogen can be used as a source of energy in fuel cells. An examination of some thermodynamic factors showed that higher CO2 turbine inlet pressure has an optimum value in producing fresh water and hydrogen, while the higher CO2 turbine inlet temperature slightly reduces the productions rate. The more recovery ratio also causes a sharp reduction in hydrogen production, whereas it has an optimum amount of fresh water production at recovery ratio equals to 0.47.

A Monte Carlo approach to the ship-centric Markov decision process for analyzing decisions over converting a containership to LNG power

A Monte Carlo approach to the ship-centric Markov decision process (SC-MDP) is presented for analyzing whether a container ship should convert to LNG power in the face of evolving Emission Control Area regulations. The SC-MDP model was originally developed as a means to analyze uncertain, sequential decision making problems. However, the original model is limited in its handling of uncertainty by only using discrete probabilistic values to account for the uncertainty. This paper extends the model to include Monte Carlo simulations to gain a deeper understanding of how uncertainty affects decision making behavior. A case study is presented involving the impact of evolving Emission Control Areas on the design and operation of a notional 13,000 TEU container ship. The decision of whether to invest in a dual fuel LNG engine is analyzed given uncertainties in economic parameters, regulatory scenarios, and supply chain risks. The case study is used to show how variations in uncertain parameters can have a drastic effect on optimal decision strategies.

The Effectiveness of New Power Generation and Energy Demand Reduction to Achieve Greenhouse Gas Reduction Goals in Building Area

Since the massive power outages that hit across the nation in September 2011, a growing imbalance between energy supply and demand has led to a severe backup power shortage. To overcome the energy crisis which is annually repeated, a policy change for deriving energy supply from renewable energy sources and a demand reduction strategy has become essential. Buildings account for 18% of total energy consumption and have great potential for energy efficiency improvements; it is an area considered to be a highly effective target for reducing energy demand by improving buildings’ energy efficiency. In this regard, retrofitting buildings to promoting environmental conservation and energy reduction through the reuse of existing buildings can be very effective and essential for reducing maintenance costs and increasing economic output through energy savings. In this study, we compared the energy reduction efficiency of national power energy consumption by unit production volume based on thermal power generation, renewable energy power generation, and initial and operating costs for a building retrofit. The unit production was found to be 13,181GWh/trillion won for bituminous coal-fired power generation, and 5,395GWh/trillion won for LNG power generation, implying that LNG power generation seemed to be disadvantageous in terms of unit production compared to bituminous coal-fired power generation, which was attributable to a difference in unit production price. The unit production from green retrofitting increased to 38,121GWh/trillion won due to the reduced energy consumption and benefits of greenhouse gas reduction costs. Renewable energy producing no greenhouse gas emissions during power generation and showed the highest unit production of 75,638GWh/trillion won, about 5.74 times more effective than bituminous coal-fired power generation.

Improving Electricity Access in Ghana Challenges and the Way Forward

Growth in demographic requirements, increased urbanization and rural electrification coupled with an ever-increasing technological demand, and the aspiration to transform into a middle-income country have led to a fast growth in energy demand in the past two decades in Ghana. Yet there is a huge deficit in supply and this has become a major limitation to growth and quality of life. As Ghana has devoted itself to universal access to electricity by 2020, the real challenge is in reaching the capacity to meet this goal; and most importantly, ensuring that supply is adequate and reliable. With access to electricity in Ghana been low for some time now with no improvement in sight, there is the need for a study such as this. The paper sought to examine the challenges preventing the progress of accessible electricity in Ghana. The paper adopted a systematic review approach and used publications that focused on or related to the subject understudy. Key findings identified in the paper include; poor pricing, increasing demand and supply shortfalls coupled with irregularities, institutional restrictions, lack of credible off-taker and lack of policy and project continuity. To address these challenges, suggested recommendations include; exploring all means of getting power source, including LNG, Solar, landfill gas and nuclear power, establishing a vibrant and robust power ministry that can help reform and also help in revenue collection.

ICOPE-15-1020 Hampson type heat-exchanger technology and economic evaluation for LNG re-gasification and power generation At LNG receiving terminals

The system for high utilization of LNG cold energy is proposed by use of process simulator. The proposed design is a closed loop system, and composed by a Hampson type heat exchanger, turbines, pumps and advanced humid air turbine (AHAT) or Gas turbine combined cycle (GTCC). Its heat sources are Boil-off gas and cooling water for AHAT or GTCC. The higher cold exergy recovery to power can be about 38 to 56% as compared to the existing cold power generation of about 20% with a Rankine cycle of a single component. The advantage of the proposed system is to reduce the number of heat exchangers. Furthermore, the environmental impact is minimized because the proposed design is a closed loop system. A life cycle comparative cost is calculated to demonstrate feasibility of the proposed design. The development of the Hampson type exchangers is expected to meet the key functional requirements and will result in much higher LNG cold exergy recovery and the overall system performance i.e. re-gasification. Additionally, the proposed design is expected to provide flexibility to meet different gas pressure suited for the deregulation of energy system in Japan and higher reliability for an integrated boil-off gas system.

Exergy analysis of a combined power cycle using low-grade heat source and LNG cold energy

This paper presents a comparative exergy analysis based on the second law of thermodynamics for a combined power generation cycle using a low grade heat source and LNG cold energy. The combined cycle consists of a LNG power cycle and an ammonia-water Rankine cycle with (R) and without regeneration (S). The effects of system parameters on the exergy destruction at each component as well as the total exergy efficiency are investigated extensively. A characteristic exergy efficiency-work diagram is proposed to consider the two system variables simultaneously. The results indicate that the thermodynamic performance of the combined system is strongly affected by the system parameters. Under the typical operating conditions for a heat source of 200°C, calculated optimal exergy efficiencies are 22.0% (S) and 21.4% (R) for the condensation temperature at Tc = 40°C, and 27.0% (S) and 28.5% (R) for Tc = −20°C.

302 次世代LNG気化発電システムの提案(FM-1 持続可能社会におけるものづくり)

302 次世代LNG気化発電システムの提案(FM-1 持続可能社会におけるものづくり)

Study of LNG Vaporization and Power System for the Next Generation

Study of LNG Vaporization and Power System for the Next Generation

Analysis on Service Life of Hot-end Components of Gas Turbine Using Equivalent Operation

The reliability of the gas turbine depends on the technical status and the maintenance level of the hot-end components in a large part.The three main factors influencing on the service life of the hot-end components of the gas turbine were analyzed first.On this basis,various common service life assessment methods for gas turbine were discussed in detail.Aiming at the features of the M701F gas-steam combined cycle unit in Huizhou LNG power plant,a gas turbine life assessment method based on equivalent operation time analysis was put forward.The calculation result of an example shows that the equivalent operation time analysis method is a simple and practical assessment method. DOI: http://dx.doi.org/10.11591/telkomnika.v11i3.2229 Full Text: PDF

Evaluation of CO 2 free electricity trading market in Japan by multi-agent simulations

As of November 2008, a new market, the CO 2 free electricity market, started pilot trading within the Japan Electric Power Exchange (JEPX). The electricity in this market comes from renewable resources, nuclear or fossil thermal power with CDM credits. The demanders of the CO 2 free electricity are supposed to be the power companies with high emission rates. In this paper, we analyzed the effects of the new market by using a multi-agent based model to simulate the markets. From our simulation results, we found that the demander, under strict CO 2 emission regulations, tends to buy more electricity from the new CO 2 free market even though the price of this market is higher than that of the normal power exchange market. Suppliers with hydro or nuclear power plants only sell their electricity to the CO 2 free market, and suppliers with coal power plants also enter this market (with CDM credits). The media and peak demands in the normal market are met mainly by electricity from LNG power plants. We also compared the results from the multi-agent approach with those from the least-cost planning approach and found that the results of the two methods were similar.

Coal seam gas production: the operational and maintenance challenges

Compared to conventional gas, coal seam gas (CSG) production introduces additional complexities in operation due to the remoteness, number and distribution of the producing wells, the quantity of associated water and the variability in characteristics of each well. The potential irregularity in gas production is further highlighted when integrating with relatively steady state downstream facilities such as LNG production and power generation. Margins are particularly sensitive to operating cost because of the remoteness and distributed nature of the producing assets. Cost effective and reliable production of gas to the flow tolerances needed downstream requires that operations management, ongoing field development, asset maintenance and regulatory compliance be systematic and highly integrated. Experience shows that for operations reliant on distributed and remote assets, including CSG, that the ratio of predictive/preventive to corrective maintenance correlates directly to surety of gas production, with little margin to compensate for less than required reliability or low maintenance productivity. For CSG production it is difficult to avoid significant lost production as a consequence of higher levels of unplanned asset downtime. The remoteness, number of assets and operating cost constraints simply makes it difficult to overcompensate for lower reliability. Corrective actions are significantly more expensive when compared with centrally located assets because of the heightened pressure to correct in the shortest possible time. Further, deterioration of the maintenance regime compounds the effect as the emerging backlog of critical issues reduces the ability of crews to keep up with the preventative maintenance programme. Achieving a reliable outcome in CSG operations is therefore more reliant on a robust operations and maintenance management arrangement that also effectively incorporates the ongoing discrete activities of drilling, well completions, start-up and abandonment. To achieve these outcomes operators must ensure: the early development of maintenance philosophies, systems and processes during the project phase that consider the frequency of field variations for life of asset; a well planned system start up, commissioning and transition into first production; and, a constant focus on efficient deployment of resources, fit for purpose reliability and maintenance routines, logistics support and sparing plans, use of appropriate remote monitoring technologies and an incorporated regulatory compliance management plan. In its presentation PSN will demonstrate, through case study examples from its operations supporting coal seam gas and gas production assets in the United States and distributed and remote assets for the Western Australian Water Corporation, the challenges and management focal points critical to effective CSG production. The case studies will demonstrate the benefits achieved by PSN’s operations and maintenance management approach in the following areas: operations and maintenance readiness; distributed asset management; managing field development and modifications; implementing high performance maintenance; environmental monitoring and compliance; resource utilisation models; and, workforce training and development

퐁력전원이 피크타임과 발전설비구성에 미치는 영향분석: 제3차 신재생에너지 기술개발 및 이용.보급 기본계획 기준

Although renewable power is regarded a way to active response to climate change, the stability of whole power system could be a serious problem in the future due to its uncertainties such as indispatchableness and intermittency. From this perspective, the peak time impact of stochastic wind power generation is estimated using simulation method up to year 2030 based on the 3rd master plan for the promotion of new and renewable energy on peak time. Result shows that the highest probability of wind power impact on peak time power supply could be up to 4.41% in 2030. The impact of wind power generation on overall power mix is also analyzed up to 2030 using SCM model. The impact seems smaller than expectation, however, the estimated investment cost to make up such lack of power generation in terms of LNG power generation facilities is shown to be a significant burden to existing power companies.

Significant benefits with a cylindrical hull for FPSO, drilling, LNG, and offshore power plant applications

Significant benefits with a cylindrical hull for FPSO, drilling, LNG, and offshore power plant applications

의사결정의 최적화를 위한 환경·경제성 통합분석

In order to support decision making of energy related policies of government and industry, intergrated environment & economic analysis applying the BEES(Building for Environmental and Economic Sustainability, Lippiatt) model has been tried to simulate for finding the best alternatives of energy resources such as coal, oil, and LNG. To achieve this aim, LCA tool has been applied to the environmental analysis based on ISO14040's, while the unit price for generating 1GWh electricity including construction cost, operating cost, and fuel cost has been considered for the economic analysis. Integrated environment & ecomomic analysis is based on the result of simulation according to relative weigting of environment and economic importance. As the result of research, LNG over thirty percent in environmental weighting(seventy percent in economic with regard to relative importance) is the best fuel resource for generating electricity, when the operating rate of power plant is the sixty percent. Furthermore, the higher environmental weighting in relative importance is, the better integrated environment and economic result to LNG power plant is.